The search for water filters to provide better quality drinking water has taken many paths. While many of these paths have improved certain aspects of the water quality to date, there remain many unsolved problems.
There have been a variety of canister type in-line water filter system with replaceable filters, such as those produced by Cuno Inc. and marketed under the trademark AQUA-PRO.RTM.. While these in-line canisters allow one to replace the filter element, the spent filters have a residue deposited on the surface making handling at best distasteful and discouraging recycling of the filter which requires extensive handling.
The problem of surface residue has, in part, been overcome by disposable counter-top units, such as those produced by Herbalife International Inc. However, the difficulty with such units is that they require counter space which, in the kitchen environment, is at a premium. Furthermore, these counter top units are designed to be totally disposable and thus do not encourage recycling of the spent units. There are also other counter-top units, such as described in U.S. Pat. No. 4,717,476, which employ replaceable filters. However, these units require disconnecting and reconnecting of water lines when replacing the filter.
Some of the filters described in the filtration units discussed above employ silver impregnated activated charcoal to eliminate bacterial contamination. These filters reduce the bacterial contamination in drinking water, however they place residual silver in the water and silver is a contaminant.
Thus, there is a need for a filtration system that provides an in-line system, of which the filter can be conveniently removed, and encourages recycling of the filter unit. In addition, there is a need for a system where the silver can be readily employed to remove bacterial contaminants, without residual silver being left in the water.